U.S. home owners are refinancing their mortgages at the fastest clip since 2005, but the difference now is they are putting cash in, not taking it out.

At the going rate, 25% of all first-lien U.S. mortgages will be refinanced this year, according to LPS Applied Analytics. That represents about $7.1 billion — just through June of this year — in savings on monthly payments, according to economists at Freddie Mac, who ran the numbers for this report.